Propeller.



No.864, 190. 7. PATENTED AUG. 27, 1907.

J. H. PIERGE,

' PROPELLER.

uruornol 17mm mm, 1007.

' 2 sums-4mm 2.

wlmigg I i If: NTOR A TORNEY UNITED STATES PATENT OFFICE.

JAMES H. PIERCE. OF BAY CITY, MICHIGAN, ASSIGNOR TO SMALLEY MOTORCOMPANY, LIMITED, OF BAY CITY, MICHIGAN.

PROPELLER.

Patented Aug. 27, 1907.

Application filed January '7, 1907. Serial NO- 351,209-

ii To all whom it may concern:

Be it known that JAMES H. PIERCE, a citizen of the United States,residing at Bay City, in the county of Bay and State of Michigan, hasinvented certain new and useful Improvements in Propellers; and he doeshereby declare the following to be a full, clear, and exact descriptionoi' the invention, such as will enable others skilled in the art towhich it appertains to make and use the same.

My invention relates to propellers, one object being to provide a deviceof this character wherein the drag on the propeller caused by the deadwater lying between the blades is avoided.

Another object is the provision of means for more easily and quicklyaccomplishing the reversal of the blades with a less expenditure ofstrength than here tofore. p

A further object is the provision of a propeller having a hub adapted toreceive the shanks of the propeller blades passing diametricallytherethrough, whereby a larger bearing is afforded the shanks and thesize of the hub reduced, as well as affording a better leverage forreversing the blades. 1

A still further object is the provision of an approximately cylindricalhub which does not tear up the water to any appreciable extent.

Still another object is the provision of a bearing in the hub to receivea longer shank which is locked to the hub at that end opposite theblade, whereby a long journal bearing is afforded and the strain andstress on the parts reduced.

A further object is the provision of a propeller comprising a solid hub,the inner end of which is secured to the outer end of the shaft withoutthe use of screw threads, the hub being apertured diametrically toreceive the shanks of the blades.

Another object is the provision of a propeller blade in combination withits hub, the blade having a long neck or shank to afford a longerbearing surface and resist the strain caused by the turning of the bladein the water.

To these and other ends, therefore, my invention consists in certainnovel features and combinations, all of which will be more fullydescribed hereinafter, and particularly pointed out in the claims.

In the accompanying drawings, Figure 1 is a side view of my invention,Fig. 2 is a longitudinal cross sectional view therethrough, Fig. 3 is atop plan view of the propeller, Figs. 4 and 5 are detail views of theyoke, Figs. 6 and 7 are detail views of the shank and propeller blade,and Figs. 8 and 9 are detail views of a modified means for securing theshanks in position.

(A) indicates the rear end of the propeller shaft receivable in theforward end of the propeller hub (B),

to which it is keyed, as shown, and I may also secure the hub and shafttogether by means of a tapered pin (0) to prevent accidentaldisconnection, the pin being easily driven out, its ends lying flushwith the grooves (1) and (2), hereinafter described.

The propeller hub is approximately cylindrical and has two parallellongitudinally extending grooves (1) (2) formed therein, the groovesbeing located on opposite sides of the hub and somewhat out of directalinement with each other. Furthermore, the groove (1) is longer thanthe groove (2). A yoke comprising a collar (3) slidable on the propellershaft and arms (4;) (5) projecting from the collar is provided, the armsbeing of different lengths and lying out of lateral alinement with eachother. These arms are received in the respective guide grooves (1) (2),and at their ends are provided with the oppositely projecting pins (6)(6), for a purpose hereinafter set forth. The yoke is connected with alever (not shown), whereby the yoke is reciprocated on the shaft (A).

The propeller hub is provided with the parallel apertures (7) (7)passing diametrically therethrough from side to side, one of theapertures being in advance of the other, and while I have illustrated atwo-bladed propeller, the number of blades may be increased withoutdeparture from the invention. These apertures passing diametricallythrough the hub afford a long journal bearing for the shanks of thepropeller blades, thus permitting the use of a long shank and obtaininga better leverage from the longitudinal center of the shank to the pin(6) on the yoke arm, which advantage cannot be obtained by incasing therear end of the shaft in the hub and mounting the short shanks in thecasing.

It will be observed that I do not extend the shaft through the hub, andhence I am able to aperture the hub centrally and extend the shankstherethrou'gh. The advantage thus obtained is considerable, since thereis a great strain on the blades when turning in the water and a shortneck or shank would be liable to snap or break off, whereas the longbearing resists the strain. Furthermore, by mounting the bladescentrally of the hub rather than offset or tangentially, I reduce thevibration imparted to the vessel, and at the same time reduce the strainon the blades while obtaining just as effective operation or contactwith the water. Also by mounting one blade in advance of the other, Ireduce the amount of drag on the propeller causedby the dead waterbetween the blades. Again the offset arms (4) and (5) enable me toprovide an approximately cylindrical hub which will not break up thewater during rotation, and also permits the use of a smaller hub thancould be employed if the yoke was incased within the hub.

By keying the inner end of the hub to the rear end of the shaft, I avoidthe necessity of threading the parts, which is more laborious and alsocreates a liability of working loose.

The propeller blades (8) (8) project from opposite sides of the hub, oneblade lying in advance of the other. The shanks of the blades arecylindrical, and journaled in the respective apertures (7 (7), and Iprefer to cut away the ends of the shanks to leave the oppositelylocated segmental flanges (9) (9), an annular groove (10) being formedon the end of the shank behind the flanges.

The apertures (7) (7) are provided with segmental ribs (ll) (11) locatednear, but preferably not at the opposite inner ends of the apertures.The shanks are inserted into the apertures from the outer ends, the ribsand flanges being so located relative to each other that the shanks canonly be received in the apertures when the blades occupy an abnormalposition, the flanges passing between the ribs, after which the shanksare given a quarter turn, whereby they are locked in position. Thus theshanks are permitted an oscillatory movement in the apertures to reversethe propeller blades without danger of becoming disengaged from theapertures, since the stationary ribs in such apertures project into theannular grooves in the shanks at all times when the blades are in normalposition and lie against the flanges.

Instead of using the segmental ribs and flanges, however, I may use theconstructions shown in Figs. 8 and 9, wherein the shanks are provided,near, but not at their ends, with semicircular peripheral grooves (14),and tapered keys (15) are driven through the hub tangentially of theshanks in such manner as to enter the grooves to permit rotary, but notlongitudinal movement of the shanks.

Located at the juncture of the shank and blade of each propeller bladeis a laterally extending foot (12) slotted at its outer end, as shown at(13), the foot limiting the inward movement of the shank and lying justoutside the aperture. This foot is of such length that its outer or freeslotted end lies adjacent one of the pins (6), which is receivable inthe slot. Thus the reciprocation of the yoke will operate to partiallyrotate the shanks and shift or reverse the inclinations of the bladeswhen going ahead or backing.

The collar (3) lies close to the end of the hub when the boat is goingahead, so that no sticks, leaves or other extraneous material can lodgebetween the hub and collar, and in View of the fact that the boat isgenerally traveling forwardly, this operates to reduce the resistanceoffered the Water during the rotation of the propeller. In goingbackward, the collar is moved forwardly drawing the arms therewith andcausing a partial rotation of the shanks to reverse the inclination ofthe blades. It will be observed that the yoke arms lie outside the huband are not incased therein.

To remove the blades, all that is necessary is to slide the yokeforwardly far enough to Withdraw the pins (6) (6) from the slots (13)(13) of the feet, whereupon the feet and shanks can be turned until theflanges on the shanks register with the spaces between the ribs of theapertures, so as to permit the withdrawal of either or both of theshanks. Or if the tapered keys (15) are employed for fastening theblades and shanks to the hub, all that is necessary is to knock out thekeys, whereupon the blades may be freely removed and replaced.

From the foregoing, it is evident that I have devised a simple compactpropeller, wherein the disadvantages of former constructions have beenobviated and the cost reduced, as well as obtaining advantages andcombinations not hitherto disclosed.

Having thus fully disclosed my invention, what l claim as new is 1. In apropeller, the combination with a shaft, of an approximately cylindricalhub secured to the extreme rear end of the shaft and extendingrearwardly of the shaft, the hub provided with diametrically extendingapertures, one located in advance of the other and passing centrally ofthe hub. shanks oscillatory within the apertures. blades carried by theshanks, the hub provided with olfset grooves of different lengths, armsof unequal lengths slidingly received in the respective grooves, acollar slidingly mounted on the shaft, the collar normally lying againstthe forward end of the hub. the arms connected to the collar pinscarried by the arms, and laterally projecting feet located at thejuncture of the shanks and blades, the outer ends or the feet beingslotted to receive the pins on the arms, the reciprocation of the armsoperating to reverse the propeller.

2. A propeller comprising a shaft. an approximately cylindrical hubsecured to the rear end of the shaft whereby the latter does not extendlongitudinally through the hub, the hub provided with solidbearings-extending diametrically and continuously therethrough from sideto side, pro peller blades. shanks carried by the blades. the shanksreceived in the bearings, operating means located exterierly of the hub,and means carried by the blades exteriorly of the hub with which meansthe operating means engages to reverse the blades.

In a propeller, the combination with a shaft, of a hub secured"theretoand provided with apertures. blades, shanks carried by the blades andjournaled in the apertures. the hub provided exterior-1y of itself withoppositely located longitudinally extending grooves of varying lengthsoffset relative to each other, a collar slidable on the shaft, oilsetarms of varying lengths carried by the collar and receivable in therespective grooves and means connecting the arms and shanks to oscillatethe latter.

4. In a propeller, the combination with a shaft, 01' a hub securedthereto and extending rcarwardly of the shaft, the hub provided withdiametrically extending apertures, on located in advance of the other,segmental ribs located near the respective inner ends ofthe apertures,shanks journaled in the apertures, segmental flanges carried by theshanks and adapted to pass between and lie against the segmental ribs inthe apertures, blades carried by the shanks and means for oscillatingthe shanks in the apertures to reverse the blades.

In a propeller, the combination with a shaft, of a hub secured to theouter end thereof, the hub provided with diametrically extendingaperturcs, one located in advance of the other, shanks journaled in theapertures and having peripheral grooves near their respective innerends, tapered keys passing transversely through the hub and intersectingthe peripherahgrooves, blades carried by the shanks and means forreversing the blades.

In testimony whereof, he allixes his signature in presence of twowitnesses,

JAMES H. PIERCE.

Witnesses Gno. I3. Wrmcox, RALPH S. WARFIELD.

